Linux基础——通过select实现简单的服务器与客户端

                  1 #include <stdio.h>
  2 #include <stdlib.h>
  3 #include <string.h>
  4 #include <sys/stat.h>
  5 #include <sys/types.h>
  6 #include <fcntl.h>
  7 #include <sys/time.h>
  8 #include <sys/select.h>
  9 #include <errno.h>
 10#define ON 1
 11#define OFF 0
 12int errno;
 13 typedef struct tag
 14{
 15int id;
 16int fd;
 17int type;
 18}NODE;
 19int main(int argc, constchar *argv[])
 20{
 21if(mkfifo(argv[1], 0666) == -1)
 22    {
 23         printf("创建管道失败!!n");
 24         exit(1);
 25    }
 26 27int fd;
 28     fd = open(argv[1], O_RDONLY);
 29if(fd == -1)
 30    {
 31         printf("open error!!n");
 32         exit(1);
 33    }
 34     NODE list[1024];
 35int i;
 36for(i = 0; i< 1024; i ++)
 37    {
 38         list[i].id = 0;
 39         list[i].type = OFF;
 40         list[i].fd = 0;
 41    }
 42    fd_set readset, ready;
 43     FD_ZERO(&readset);
 44     FD_ZERO(&ready);
 45     FD_SET(fd, &readset);
 46struct timeval tm;
 47char buf[128];
 48int ret;
 49while(1)
 50    {
 51         ready = readset;
 52         tm.tv_sec = 0;
 53         tm.tv_usec = 1000;
 54         ret = select(fd + 1, &ready, NULL, NULL, &tm);
 55if(ret == 0)
 56continue;
 57elseif(ret == -1)
 58        {
 59if(errno == EINTR)
 60continue;
 61break;
 62        }
 63else 64        {
 65             memset(buf, 0, 128);
 66             read(fd, buf, 128);
 67if(strncmp(buf, "on", 2) == 0)
 68            {
 69int sfd;
 70char name[128];
 71                 memset(name, 0, 128);
 72                 sscanf(buf + 3, "%d", &sfd);
 73                 printf(" %d is on !!n", sfd);
 74                 sprintf(name, "%d.fifo", sfd);
 75int index;
 76for(index = 0; index < 1024; index ++)
 77                {
 78if(list[index].type == OFF)
 79                    {
 80                         list[index].id = sfd;
 81                         list[index].fd = open(name, O_WRONLY);
 82                         list[index].type = ON;
 83break;
 84                    }
 85                }
 86            }
 87elseif(strncmp(buf, "off", 3) == 0)
 88            {
 89int sfd;
 90                 sscanf(buf + 4, "%d", &sfd);
 91                 printf("%d is off !!n", sfd);
 92int index;
 93for(index = 0; index <1024; index ++)
 94                {
 95if(list[index].id == sfd)
 96                    {
 97                        close(list[index].fd);
 98                         list[index].id = 0;
 99                         list[index].type = OFF;
100break;
101                    }
102                }
103            }
104else105            {
106int sfd;
107                 sscanf(buf + 5, "%d", &sfd);
108int index;
109for(index = 0; index < 1024; index ++)
110                {
111if(list[index].type == ON && list[index].id != sfd)
112                        write(list[index].fd, buf, strlen(buf));
113                }
114            }
115        }
116    }
117    close(fd);
118     unlink(argv[1]);
119return0;
120 }

                 1 #include <stdio.h>
 2 #include <stdlib.h>
 3 #include <string.h>
 4 #include <sys/stat.h>
 5 #include <sys/time.h>
 6 #include <sys/types.h>
 7 #include <sys/select.h>
 8 #include <fcntl.h>
 9int main(int argc, constchar *argv[])
10{
11char name[128];
12     memset(name, 0, 128);
13     sprintf(name, "%d.fifo", getpid());
14if(mkfifo(name, 0666) == -1)
15    {
16         printf("创建管道失败!!n");
17         exit(1);
18    }
19int fd;
20     fd = open(argv[1], O_WRONLY);
21if(fd == -1)
22    {
23         printf("open error!!n");
24         exit(1);
25    }
26char buf[128];
27     memset(buf, 0, 128);
28     sprintf(buf,"on %dn",getpid());
29    write(fd, buf, strlen(name));
30int sfd;
31     sfd = open(name, O_RDONLY);
32if(sfd == -1)
33    {
34         printf("open error!!n");
35         exit(1);
36    }
37if(fork() == 0)
38    {
39if(fork() == 0)
40        {
41            close(fd);
42while(memset(buf, 0, 128), read(sfd, buf, 128))
43                 printf(" >> %sn", buf);
44            close(sfd);
45             exit(1);
46        }
47         exit(1);
48    }
49    wait(NULL);
50    close(sfd);
51while(memset(buf, 0, 128), fgets(buf, 128, stdin) != NULL)
52    {
53char msg[128];
54         memset(msg, 0, 128);
55         sprintf(msg, "from %d: %s",getpid(), buf);
56        write(fd, msg, strlen(msg));
57    }
58     memset(buf, 0, 128);
59     sprintf(buf, "off %dn", getpid());
60    write(fd, buf, strlen(buf));
61    close(fd);
62    unlink(name);
63return0;
64 }